Pre-spin device for rocket launcher



Dec. 25, 1956 c. R. VE GREN 2,775,163

PRE-SPIN DEVICE FOR ROCKET LAUNCHER Filed May 7, 1952 2 Sheets-Sheet l ii ulli 49M INVENTOR 3 4 CONRAD R.VEGREN $44M 6. WM

ATTORNEYS Dec. 25, 1956 c. R. VEGREN 2,775,163

FREE-SPIN DEVICE FOR ROCKET LAUNCHER Filed May 7, 1952 2 Sheets-Sheet 2 ATTORNEY-5 Unite PRE-SIIN DEVICE, FOR ROCKET LAUNCHER Conrad R. Vegren, Washington, D. C.

ApplicationMay; 7, 1952, Serial No. 286,589

4 Claims; (Cl; 891.7) (Granted underTifle 35; U. 5. Code (1952), sec.'.266)'1 The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor-.-

This invention relates to spin stabilized rockets and more particularly to launching apparatus for imparting pre-spin to the rockets .prior to. release thereof from the launchingapparatus.

In the prior art certain types of rockets have been constructed to spin about their longitudinal axes, which latter is coincident with the trajectory or path of flight, this for the purpose of stabilizing same. The spin is attained by canting the gas discharge nozzles at the rear end of the rocket in such manner to produce torque, acting circumferentially about the rocket axis. In this type of rocket the spin commences upon release within its launching tube and accelerates as it passes through the tube and during at least a portion of its free flight after launching. The forward velocity upon leaving the launching tube is relatively low as is also the rate of spin which factors are not conducive to produce optimum conditions of stability during the initial launching period. This invention improves the stability of the rocket during said initial launching period by increasing the rate of spin thereof.

One of the objects of the invention is to provide a launcher for pre-spinning a spin-stabilized rocket prior to its release along the launcher.

Another object is to automatically release the rocket from a launcher tube for axial movement therealong after it has attained a predetermined rate of spin therein.

Another object is to release the rocket by mechanism actuated by the issuing gaseous products of combustion of the rocket.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawing wherein:

Fig. 1 is a fragmentary side elevation of the rear end of a launching tube, portions being broken away to reveal a portion of a rocket therein, and the pre-spin device which constitutes the subject of the invention;

Fig. 2 is an enlarged section taken on line 2-2, Fig. 1;

Fig. 3 is a fragmentary view of a portion of the internal details of the device as viewed in the direction of arrow 3, Fig. 1;

Fig. 4 is a section taken on line 44, Figs. 1 and 3; and

Fig. 5 is a section taken in line 55, Figs. 1 and 3.

Referring in detail to the drawing, and particularly Fig. 1, a rocket launcher 10, illustrated in the form of a tube open at opposite ends thereof, contains a rocket 11, comprising a tubular wall 12, to which is secured in any desired manner, such as by flange 13 and threaded sleeve 14, a wall 15 having a plurality of exhaust nozzles 16, the axes of the nozzles being canted, as best shown in Figs. 3 and 4 to impart spin to the rocket about its longitudinal axis during flight along the trajectory there- Patented Dec. 25, .1956

2 of. The constructionrsofar described is conventional and well known and'it will-be understood thatttie rockiet may contain any suitable combustible material 'for propelling sameand any suitable ignitionmeans rriay'be'employed. to ignite'theicombustible material, these-features also being well known andhenceomittedfmm the di'awingjto simplify the disclosure. The"n0vel*featuresi'em'- ployed in combination. with" the" conventional construction just described will'now be set'fortlr'imdetail f" A bearing17, supported in"tubei-10,&by spider-' armsl is disposed adjacent therearendofthetube" andsuppo'rts a rotatable shaft 19, w whichis' aflixed" a-hub*2'0 carrying a plurality of 'radiallyextending vanes 21', whicli'are aflixed at their outer tips'to a sleeve 22,,the shaft 'and vane assembly beingrotatablein bearing 17f Suitable collars 23, 24 on shaft 19 'prevent'axial movementof the shaft and vane assembly.

A plurality of angularly' spaced.lugs*25"are aflix'ed to sleeve 22'and project into'sleeve14; engaging lugs 26 aflixed to sleeve 14. As best shown'inFig. 3, angular face 27, .on a lugj 25, overlaps angularface' 28,'on"a-lfi'g 26,,and it'will be apparentth'at ifatorquebeapplied to vanes 21"toeffect bodily'rotation thereof-imtliedir'ection of arrow29, lugs 25*willremain engaged with -lugs26 in the position shown and prevent forward movement' of the rocket in the direction of arrow 30. It will also be apparent that when lugs 26 move in the direction of arrow 31 at a greater angular speed than sleeve 22 in the direction of arrow 29, the lugs will disengage and the rocket will be free to move forward through the launcher tube in the direction of arrow 30.

Referring again to Fig. 3, it will be observed that axis 32 of nozzle 16 is disposed at an angle A to line 33, and that vane 21 is disposed at an angle B to line 33, angle B being greater than angle A. When gas issues in the direction of axis 32, it impinges on the vane and is deflected in a direction as indicated by line 32a, producing a. component of force 34, which tends to rotate the vanes. Due to the greater angle B than angle A, the vanes tend to rotate faster than the rocket, but since they are restrained from doing so by lugs 25, 26, it will be apparent that the lugs lock the rocket to the vanes and prevent forward movement of the rocket.

Shaft 19, rotatable with the vanes, is provided with a pair of diametrically opposed centrifugal braking devices which are identical in construction, the description of one of which will serve for both. Referring to Figs. 1 and 2, shaft 19 is provided with a transverse shaft 35, upon which slides a braking device 36, urged radially inwardly by a spring 37, and outwardly by centrifugal force. The outer surface of the braking device may be provided with high friction braking material 38 to engage the inner surface of the launcher tube.

In operation, the rocket is loaded in the launcher tube with the cooperating lugs in engagement. When the combustible material in the rocket is ignited gas issues from the discharge nozzle 16 and against vanes 21, one being provided for each nozzle. The vanes and rocket spin due to the cant angle of the vanes and nozzles, but since the cant angle of the vanes is greater than the cant angle of the nozzles the former tends to rotate faster than the latter, maintaining the lugs 25, 26 in engagement and locking the rocket against forward axial movement through the launcher tube. When a predetermined rate of spin is attained the acceleration of the vanes is checked by the centrifugal brakes engaging the launcher tube and the continued acceleration of the rocket in its spin disengages the lugs and permits the rocket to move forward through the launcher tube. It will thus be apparent that the rocket will attain a predetermined rate of spin before it is released for forward axial movement, and that its initial spin as it leaves the launcher tube will be greater than would obtain in the absence of the pre-spin mechamsm.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understod that within the scope of the appended claims the invention may be practiced otherwise than as'specifically described.

WhatIclaim is:

1. Apparatus for launching a rocket of the type having canted exhaust nozzles through which gas is adapted to issue and produce forces on the rocket to propel it along its longitudinal axis and rotate it about said axis comprising; a launcher tube adapted to contain the rocket, a rotary member disposed within the tube having vane means against which gas issuing from the rocket nozzles may impinge and effect rotation of the member, said member being rotatable in a plane normal to the longitudinal axis of the tube, the cant angle of said vanes being related tolthe cant angle of the nozzles in such manner that the member tends to rotate in said plane at a speed vin excess of the speed of rotation of the rocket, means limiting the speed of rotation of said member to obviate the tendency for it to rotate at a speed in excess of the rocket and to permit the rocket to be released from said member.

2. Apparatus in accordance with claim 1, wherein the means for locking said member and rocket together comprises at least one pair of lugs, one atfixed to the member and the other to the rocket, adapted to interlock while the member tends to rotate at a speed in excess of they prises at least one pair of lugs, one aflixed to the member and the other to the rocket, adapted to interlock while said member tends to rotate at a speed in excess of the speed of rotation of the rocket and release when the rocket rotates at a speed in excess of the speed of rotation of said member, said means for releasing the member from the rocket including a oentrifugally actuated braking device carried by the member.

References Cited in the file of this patent UNITED STATES PATENTS 2,701,984 Terce Feb. 15, 1955 FOREIGN PATENTS I 457,201 Italy May 12, 1950 912,398 France Aug. 7, 1946 30 1,011,653 France Apr.,9, 1952 

